[Feature Request] Ability to combine multiple cap recordings into a single recording in editor

[Suhasnama]

Current Behavior :
Currently the cap editor doesn't support adding another cap recording in a editor session.

Expected Behavior :
While editing a cap recording , I should be able to import one or more other cap recordings in the editor & create a single video file out these multiple recordings.

Just like how currently cap supports Keyboard track , captions track similarly we should be able to add recording track & edit them

[linear]

CAP-675

[tembo]

There's some relevant context in the codebase for this feature request:

Existing Track System
The editor already supports multiple track types through TimelineTrackType in apps/desktop/src/routes/editor/context.ts:114-121 - currently clip, caption, keyboard, text, zoom, scene, and mask. The TrackManager component (apps/desktop/src/routes/editor/Timeline/TrackManager.tsx) already has infrastructure for adding/toggling tracks and even supports supportsMultiple for tracks that can have multiple instances.

Multi-Segment Architecture
Cap already handles multiple recording segments internally - see MultipleSegments and SingleSegment types which support pause/resume recording (fixed in PR #1514). The rendering pipeline in crates/rendering/src/project_recordings.rs processes these segments with SegmentRecordings structs that include display, camera, mic, and system audio per segment.

Related Open Issue
Issue #899 "Backend for importing videos" (tracked as CAP-444) appears related - it seems like foundational work for importing external videos would be needed to support combining recordings from different Cap projects.

Implementation Considerations
The main challenges would likely be:

1. Adding a mechanism to import/reference recordings from other Cap projects
2. Extending the timeline segment model to track which project/recording each segment originates from
3. Handling potentially different recording configurations (resolution, frame rate, audio tracks) between combined recordings
4. UI for browsing and selecting recordings to combine - the SceneTrack pattern (apps/desktop/src/routes/editor/Timeline/SceneTrack.tsx) could serve as a reference for a new "recording track" that allows adding external clips

[MinitJain]

Hey @richiemcilroy I wanted to chime in because I think there’s a simpler and more intuitive way to approach this feature.

Right now, if I want to stitch two recordings together, there’s no way to do it inside Cap. I have to leave the app entirely. What if it were as simple as being in the editor, clicking “Add Clip,” and seeing a gallery of your previous Cap recordings? You pick one (or drag it in), and it just shows up on the timeline.

Something like this:

A gallery or grid view of your existing Cap recordings so you can easily browse and select
Or even simpler, just drag and drop a recording from your Cap library directly onto the timeline

No file picker, no digging through folders. Just your recordings, right there, exactly how you’d expect it to work in something like ScreenStudio or any lightweight timeline editor.

The building blocks are already in the codebase, so I’d love to take a shot at implementing this if it gets the green light.